Much better. I'm glad you asked this question. Running the crankcase in a constant state of high vacuum can cause several issues. It can cause seal failure, oil consumption, draw in external contaminants like water/moisture, as to a degree effects piston travel. Back in the day, hot rod motors were "vacuum balanced" for this reason.

Update - while the original issue (sound after turning engine off) is fixed, now the car idles rough/erratic in park. As soon as it’s put in gear (reverse or drive) the idle picks up to normal and all is fine. Not sure if this is related to the PCV reroute but it started right after. Thanks for any input.